Cane mill



UNITED sTATEswrENT oFl-icl-z'.

HENRY HURTER, OF ST. LOUIS, MISSOURI, ASSIGNOR TO FULTON IRON WORKS COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF DELAWARE.

CANE MILL.

Specification of Letters Patent.

.Application filed November 29, 1920. SerialNo.v 427,100.

To all whom it 4may concern.

Be it known that I, HENRY HURTER, a citizen of the United States of America, a resident of the city of Louis, in the State of Missouri, have invented certain new 'and useful Improvements in Cane Mills, of

which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to improvements in cane mills and similar apparatus, including grooved rolls cooperating with each other to serve as means for crushing cane or bagasse. Prior to this invention', cane mills and cane Crushers have been provided with upper and lower rolls having circumferential ribs, and it is customary to make the ribs of the upper roll conform to-the shape and dimensions Vof the ribs on the lower roll. For example, in a three-roll mill, the circumferential ribs on all of the rolls are usually made exactly alike so that the ribs on the top roll will extend into corresponding grooves in both lower rolls, and the pitch of the ribs on these rolls is usually about' three-eights of an inch or one-half of an inch. By the term pitch as herein used, I mean the distance from the center of one peripheral rib to the center of the next adjacent rib on the same roll.

In actual practice it hasbeen found del sirable in cane mills to use rolls having small peripheral ribs, but the small grooves between these small ribs do not provide passageways large enough to quickly carry away the wave of juice which is forced backwardly into the cane, or bagasse, entering between the rolls. This is especially true of the mills which act upon the cane or bagasse while it contains a very large'percentage of the juice. When the juice laden bagasse passes between the ribbed rolls the wave of juice is discharged baekwardly on the periphery of the lower roll, and if this juice is notrapidly conducted away, it will pass into the bagasse' where it will be absorbed in relatively dry portions of the cane and then continue on with the traveling mat of crushed cane. As a consequence, some of the juice is ordinarily returned to the bagasse and can only be recovered by subsequent operations. Obviously, this reduces the capacity of the apparatus by requiring an additional operation for the extraction of juice which has been expressed from and then returned to the cane, and some of this juice is absorbed by relatively dry portions of the bagasse from which it is never recovered.

This problem has been long recognized in the art, and attempts made to carry away the juice in deep, narrow grooves formed in the lower roll. In one instance of which I am aware it was proposed to use the ordinary standard type of rolls with the usual small, V-shaped circumferential ribs, and to form a few deep narrow circumferential grooves at widely separated points in the lower roll. The usual V-shaped ribs are quite desirable, but their eiciency will be reduced if they are dispensed with at intervals to provide deep, narrow juice grooves. Furthermore, the Wave of juice cannot be most effectively conducted, away by widely separated grooves, and if the deep, narrow grooves are located very close to each other, the peripheral portions of the roll will be comparatively weak and a correspondingly weak scraper will be required for the removal of bagasse, which is firmly forced into the narrow grooves. v

Although I have referred to a wave of juice passing backwardly at the point where the mat of bagasse enters the mill, it is to be understood that this is ordinarly not an extremely large wave. In fact, the thickness of the juice wave is usually so slight that if it is divided into a larger number of very small streams on the periphery of the lower roll, the juice will cling to the roll instead of quickly dropping by gravity to the juice pan below the roll, and such streams would therefore return to the bagasse. For example, the ordinary roll is provided with numerous small V-shaped circumferential grooves located very close to each other, so the juice wave is divided into numerous small streams tending to drop by gravity on a rising surface of the roll, but the streams are so small that they will be very materially retarded by adhesion of the juice to the roll. If the juice streams were larger they would fall more rapidly and this would permit a more rapid escape of the juice from the bagasse.'

It will thus be seen that the ordinary standard V-shaped grooves and ribs of a cane mill are so small that the numerous small streams of juice cling to the lower roll and do not drop at a speed great enough to very effectively exceed the speed of the rising surface of the roll, and as a consequence some of the juice is carried back into the bagasse. This particular disadvantage might be overcome in various ways, but the object sought should be accomplished without the use of a structure having some other serious disadvantage.

I take advantage of the` possibility of dividing the juice wave int`o` comparatively few large streams which rapidly fall along the rising surface of the lower roll, instead of being materially retarded by adhesion of the juice to the roll, and this result is obtained by a new combination of elements which does not require any undesirable radical departure from the ordinary groovin of the rolls.

Briefly stated, the structure I have shown to illustrate one form of the invention 1s a three-roll cane mill, including a top roll located above and cooperating with a feed roll and a delivery roll. The cane, or bagasse, enters between the top roll and feed roll and passes out between the top roll and the delivery roll. The top roll and delivery roll may have the usual large number of small V-shaped ribs and grooves which long experience has shown to be desirable, but the feed roll is provided with relatively lar e ribs and grooves forming large canals or the juice. The wave of juice passing backwardly on the periphery of the feed roll is, therefore, divided into comparatively few large streams, which fall at a relatively high speed on the rising surface of this roll, so as to free ly escape from the mass of bagasse. All of these large grooves are open at the periphery of the roll to receive the juice at all points throughout the length of the roll. l

With the foregoing and other objects in View, the invention comprises the novel construction, combination and arrangement lof parts hereinafter more specifically described and illustrated in the accompanying drawings, wherein is shown the referred embodiment of the invention. owever, it is to be understood that the invention comprehends changes, variations and modiicatlons which come within the scope of the claims.

hereunto appended.

Fig. 1 is a vertical section illustrating a cane mill embodying the features of this invention, portions of the housing and portions of the top roll and delivery roll being broken awa Fig. 2 is an enlarged detail view showing adjacent portions of the top roll and feed roll.

Fig. 3 is an enlarged fragmentary view illustrating the condition of the crushed cane between the top roll and the feed roll.

Fig. 4 is a fragmentary view showing a portion of the feed roll and a portion of the scraper which engages the periphery of this roll. i

To illustrate the invention, I have shown a cane mill comprising a housin A and three cane-engaging rollssupporte thereby, but it is to be understood that the invention is not limited to a cane crushing apparatus of this particular type.` The rolls are arranged in a triangular group including a feed roll B, a delivery roll C, and a top roll D located between and cooperating with the rolls B and C. The top roll D and delivery roll C may be provided with the usual small V- shaped circumferential ribs l and correspondingly formed grooves 2 between the ribs. The feed roll B is provided with larger V-shaped ribs 3 extending around its periph- 80 ery, and correspondingly large V-shaped l grooves are formed between these ribs.

As an illustration of one feature of the invention, I will assume that the pitch of the small ribs 1 on the rolls C and D is one-half of an inch, and that the pitch of the ribs 3 is one inch. The rolls C and D may be provided with ribs conforming in shape and dimensions to the small ribs ordinarily found in mills of this kind, while the ribs 3 and grooves 4 are unusually large, although they ma conform to the shape of the smaller ribs an grooves. .An important distinguishin feature lies in the cooperating rolls B and having ribs of different pitch, it being customary to make the cooperating ribs of the same pitch so that the ribs on the top roll will extend into corresponding grooves in the lower roll.

Although I have shown a feed roll B having large ribs and grooves, it will be understood that-the ribs on the rolls C and D may overlap each other as shown at the right side of Fig. 1, for these small ribs 1 may be exactly alike, and -ifthe pitch of the large ribs 3 is at least twice that of the small ribs 1, it will likewise be understood that the small ribs on the top roll D can extend into the larger grooves 4 in the feed roll B. The distance from center to center of adjoining ribs 3 is 110 the same as the distance from center to center of adjoining grooves 4 which are formed alternately between the successive ribs to provide large juice canals permitting free escape of juice between all of the adjoining ribs on the feed roll B. These large adjoining canals 4 allow the juice to escape at all points throughout the length of the cane-engaging` face of the feed roll B. The grooves, or canals, 4 are wider and deeper than the 120 grooves 2, and since the ribs 3 are V- shaped in cross section, the side walls of the large grooves 4 flare outwardly at the periphery of the roll B, so the juice can readily enter and flow through these large grooves.

Figs. 2 and 3 show the large ribs 3 are disposed opposite to and extend into alternate grooves 2 in the top roll D, said top roll having intervening grooves opposite to and in alinement with the centers of the wider grooves 4. Two ribs l of the top roll extend into each wide groove 4, and the inclined side faces of the small ribs 'l are preferably parallel with the flaring side walls of the wide groove 4. The bagasse X, shown in Fig. 3, is very firmly squeezed and gripped between the upper portions of the large ribs 3 and the adjacent walls of small grooves 2. However, at the middle portion of each large groove 4 the bagasse is comparatively free, for this middle portion is in alinement with a groove in the top roll, so that bagasse is not packed into the bottoms of the juice canals formed by the large grooves 4.

To feed the cane, the rolls have a rough surface texture, and it is a well-known fact that large ribs will feed the cane more effectively than small ribs, and this is another advantage resulting from the relatively large ribs 3. The cane can be posi,- tively drawn into a. relatively small space' between the rolls B and D so as to improve the juice-expressing operation, and thereafter positively pushed into the space between the smaller ribs l of the rolls C and D. The lapping ribs 1 and 3 have sharp peripheral edges, and actual experience has shown that these sharp edges will be rough. enedin service to more effectively grip the cane, while blunt, ila-t edges would become smooth and slip along the cane. j

Instead of requiring an unusual scraper for the removal of particles of cane from the juice canals 4, I can employ the usual type of trash knife having large, strong teeth which extend the large grooves 4. 5 designates the trash knife (Figs. l and 4) located below the top roll D and having V-shaped scraping teeth 6 which extend into the large juice canals 4 and engage the walls thereof.

The rolls are rotated in the directions indicated by curved arrows in Fig. l, and the cane is fed as indicated by straight arrows. The large mat of cane entering between the rolls B and D is gradually reduced in thickness, and a wave of juice is forced back wardly onto the rising peripheral surface of the feed roll B. This body of juice is divided into comparatively few large streams which readily flow downwardly in the large juice canals 4'and drop fi'om the bottom of the roll B. The mat of cane at the point of highest compression between rolls B and D appears as suggested by Fig. 3. It is firmly wedged between the overlapping V-shaped ribs 1 and Swhere it is tightly held for the desired feeding operation, and at thesame time firmly squeezed to express the juice. The most intense gripping and squeezing action is exerted at the outer margins of the large ribs 3, and owing to the manner in which the ribs are combined with each other (Fig. 3) the crushed cane is not tightly packed into the bottoms of the large juice canals 4 and the backwardly moving wave of juice can, therefore, escape freely in these canals.

After being acted upon by the rolls B and D, the mat of crushed cane passes over the trash knife 5 and it is then forced into the space between the rolls C` and D, where it is subjected to a different crushing action. During the initial crushing operation, the mass of cane is compressed to the condition shown by Fig.'3, and duringr the subsequent operation between the rolls and D the cane is acted upon by the small uniform ribs l.

I claim:

l. A cane crushing apparatus provided Awith opposing rolls between which the cane is fed, each of said rolls being provided with circumferential cane-engaging ribs and circumferential grooves between said ribs and the pitch of the ribs on one of said rolls being greater than that of the other roll.

2. A canecrushing apparatus provided with opposing rolls between which the cane is fed, each of said rolls being provided with circumferential cane-engaging ribs and cir-` cumferential grooves between said ribs, the pitch of the ribs on one of 'said rolls being greater than that of the other roll, and all of saidv circumferential ribs and grooves being of approximately the same shape.

Y 3. A cane mill provided with upper and lower rolls between which the cane is fed, each of said rolls having circumferential cane-engaging ribs, the pitch of the ribs on said lower roll being greater than that' of the upper roll, so as to provide relatively wide juje canals in the periphery of said lower ro 4. A cane mill provided with upper and lower rolls, each of said rolls having circumferential juice-expressing ribs whereby the cane is crushed and-advanced between the rolls, the circumferential ribs of the upper roll being uniform in shape and of uniform pitch, the circumferential ribs of the lower roll being uniformly shaped and of uniform pitch, but of greater pitch than that of the upper roll, so as to provide relatively wide juice canals in the periphery of said lower roll. j

5. A cane mill provided with upper and lower rolls, each of said rolls having circumferential juice expressing ribs and circumferential grooves bewteen said ribs, the circumferential grooves in said lower roll being wider than those in the upper roll. so as to provide relatively wide juice canals in hthe periphery of said lower roll.

6. A cane mill provided with upper and lower rolls, each of said rolls havin circumferential juice expressing ribs an circumferential grooves between said ribs, the circumferential grooves in said lower roll being wider and deeper than those in the upper roll, so as to provide relatively wide and relatively deep juice canals in the periphery of said lower roll.

7. A cane mill provided with upper and lower rolls, each of said rolls having circumferential juice expressing ribs and circumferential grooves between said ribs, the circumferential grooves in said lower roll bec ing wider and deeper than those in the upper being wider and deeper than those in they upper roll, so as to provide relatively wide and relatively deep juice canals in the periphery of said lower roll, and all of said ribs and grooves being of approximately the same shape.

9. A cane mill provided with upper and lower rolls each of said rolls having circumferential juice expressing ribs and circumfer- -ential grooves between said ribs, the circumferential grooves in lsaid lower roll being wider than those in the upper roll, so as to provide relatively wide juice canals in the periphery of said lower roll, and said wide juice canals being formedalternately between the successive ribs of said lower roll to permit free escape of juice betweenl all of the adjoining ribs of the lower roll.

10. A cane mill provided with upper and lower rolls, each of said-rolls havingl circumferential juice expressing ribs and cir.- cumferential grooves .between said ribs, the circumferential grooves-in said lower roll being wider andr deeper than those in the upper roll, so as to provide relatively wide and relatively deepjuice canals in the periphery of said lower roll, the `relatively small circumferential 'grooves in said upper roll being uniform with each other and the larger grooves in said lower roll being uniform with each other, and said wide juice :anals being formed alternately between the iuccessive ribs of said lower roll to permit -ree escape of juice between all of the adoining ribs of the lower roll. c

.11. A cane mill provided' with upperjand ower rolls, each of said rolls having cir- ;umferential juice expressing ribs and cir- ;umferential grooves between said ribs, the :ircumferential grooves in said lower roll Jeing wider than those in the upper roll, so is to provide relatively wide juice canals n the periphery of said lower roll, and the listance between the centers of the adjoin- .ng ribs on said lower roll being the samev is the distance between the centers of the adf i' jacent wide canals in said lower roll.

12. A cane crushing apparatus provided with upper and lower juice expressing rolls, each of said rolls being provided with circumferential ribs approximately V-shaped in cross section, the pitch of the ribs on the lower roll being greater than that of the upper roll, so as to provide relatively large julipe canals between the ribs of the lower ro v 13. A cane mill provided with upper and lower rolls, each of said,| rolls having circumferential juice expressing ribs and circumferential grooves between Said ribs, the circumferential grooves in said lower roll beingwider and deeper than those in the upperroll, so as to provide relatively wide and relatively deep juice canals in the pe-v riphery of said lower roll, said circumferential ribs on the lower'roll being V-shaped in cross-section to form outwardly flaring walls for saidv relatively wide and deep juice canals.

14. A cane mill provided with upper and lower rolls between whichthe. cane is fed, each of said rolls having circumferential cane-engaging ribs, the pitch of the ,ribs on said lower roll being greater than that of the upper roll, so as to provide relatively wide juice canals inI the periphery of said lower roll, the comparatively large circumferential ribs on the lower roll being V- vshaped in cross-section to form outwardly flaring wallsfor said wide juice canals, and the smaller ribs on said upper roll being V- shaped in cross-section and provided Vwith sidevfaces opposite to and parallel with said flarin walls.

l5. n a 'cane mill, a feed roll, a delivery roll, a top, roll arranged above and cooperating with said feed roll and delivery roll, said feed roll and top roll being provided with circumferential cane-engaging ribs and circumferential grooves between said ribs, and the pitch of the ribs1on said feed roll being greater than that of the top roll, so as to provide relatively wide juice canals in the periphery of saidfeed roll.

416. In a cane mill, a feed roll, a delivery roll, a top roll arranged above and cooperating with said feed roll yand delivery roll, said feed roll and top roll being provided with circumferential cane-engaging ribs and circumferential vgrooves between said ribs, the circumferential grooves in said feed roll being wider and deeper than those in the top roll, so as to provide relatively Wide and relatively deep juice canals in the periphery of said feed roll.

17. In a cane mill, a feed roll, a delivery roll, a top roll arranged above and cooperating with said Vfeed roll and delivery roll, said feed roll and top roll being provided with circumferential cane-engaging ribs and roll.

grooves being of approximately the same shape.

18. In a cane mill, a feed roll, a delivery roll, a top roll arran d above and cooperating with said feed ro l and delivery roll, said feed roll and top roll being provided with circumferential cane-engaging ribs and circumferential grooves between said ribs, the circumferential grooves 41n 'sald feed roll being wider and deeper than those inthe-to roll7 so as to provide relatively wide andv re ativel deep juice canals in the periphery of said eed roll, and said juice canals being' formed alternately between the successive ribs of said feed roll to permit free escape of juice between all of the adjoining ribs of the feed roll.

19. In a three-roll cane mill, a feed'roll, a delivery roll, and a top roll arranged above and cooperating with said feed roll and deliveryy roll, each of said rolls being provided with peripheral ribs and the ribs on said feed roll being different from the ribs on said delivery roll so that a differential crushing action is exerted on the mass of cane between the last mentioned rolls and the top 20. In a three-roll cane mill, a feed roll, a delivery roll, and a top roll arranged above and cooperating with said feed roll and delivery roll, each 0f said lrolls being provided with circumferential ribs, each of said ribs being approximately V-shaped in cross-section and the roll bein di erent from that of the ribs 0n said delivery roll, so that a differential crushing action is 'exerted :on the mass of cane between the last mentioned rolls an the top roll.

21. In a cane mill, a feed roll, a delivery roll, and a top roll arranged above and cooperating with said feed roll and delivery roll, each of said rolls being provided with circumferential juice-expressing ribs and circumferential rooves between said ribs, the pitch of the 'r1bs on said top roll being the same as that of said delivery roll but less vthan the pitch of the ribs on said feed roll.

22. In a cane mill, a feed roll, a delivery roll, and a top roll arranged above and cooperating with said feed roll and delivery roll, each of said rolls being provided with circumferential j uice-expressing ribs and circumferential grooves between said ribs, the pitch of theribs on said top roll being the same as that of said delivery roll but less itch of the ribs on said feedv than the pitch of the ribs on said feed roll, the circumferential grooves in said feed roll being relatively wide and relatively deepso as to provide large'juice canals in said feed roll, and all of said circumferential ribs being V-shaped in cross section.

23. A cane crushing apparatus provided with opposing rolls between which the cane is fed, each of said rolls being provided with circumferential cane-engaging ribs, and circumferential grooves between said ribs, the pitch of the ribs on one of said rolls being greater than that of the other roll, and the relatively small circumferential ribs of one roll being extended into the larger circumferential grooves of the other roll.

24, A cane mill provided with upper and lower rolls, each of said rolls having circumferential juice expressing ribs and circumferential grooves between said ribs, the circumferential grooves in said lower roll being wider than those in the upper roll, so -as to provide relatively wide juice canals in the periphery of said lower roll, the pitch of the ribsl of said lower roll being greater than that of the upper roll and the comparatively large ribs of lsaid lower roll being extended into smaller grooves in said upper roll, said upper-roll bemg provided with intervening grooves opposite to the wider said lower roll. f

25. A cane mill provided with upper' and lower rolls, each-of said rolls having circumferential juice expressing ribs and circumferential grooves between said ribs, the circumferential groovesin said lower roll being' wider than those in the upper roll, so as to provide relatively wide juice canals in the periphery of said lower roll, the pitch ofthe ribs on said lower roll being at least twice the pitch of the 'ribs on said upper roll.

26. A cane mill provided with upper and lower rolls, each of said rolls having circumferential juice ex ressing ribs and circumferential grooves etweenfsaid ribs, the circumferentlal grooves in said lower roll being wider than those in the upper roll, So as to provide relatively Wide juice canals 'in the periphery of saidllower roll, the pitch of the ribs on said lower roll being at least tw-ice the pitch of the ribs on said upper roll, all of 'said ribs being V-shaped in cross-section and the comparativel large ribs of said lower roll being exten ed into alternate grooves of said upper roll, said upper roll having intervening grooves opposite to and in alinement with the centers of the wider grooves in said lower roll. v

In testimony that I claim the foregoing I hereunto aix my signature. v

HENRY HURTER.

grooves in 

